Telephone instrument



J. S. TIMMONS TELEPHONE INSTRUMENT June 16, 1925v Filed June 28, 1921 2 Sheets-Sheet 1 I Juhe 16, 1925.

J. S. TIMMONS TELEPHONE INSTRUMENT Filed June 28, 1921 2 Sheets-Sheet 3 Patented June 16, 1925.

JOHN S. TIMMONS, 0F PHILADELPHIA, IPENITSYLVANIA.

TELEPHONE INSTRUMENT.

Application filed June 28, 1921. Serial No. 481,040.

To all whom it may concern:

Be it known that I, Join: S. Tmurons, a citizen of the United States, residing in Philadelphia, Pennsylvania, have invented Telephone Instruments, of which the fol lowing is a specification.

One object of this invention is to provide relatively simple and substantial means for adjusting a telephone transmitter or receiver tochange the tone and pitch of the instrument or for the purpose of causing it to operate at the highest efficiency.

A further object of the invention is to provide a telephone instrument with means whereby the above adjustment may be made under operating conditions and from the outside of said instrument.

These objects and other advantageous ends I attain as hereinafter set forth, reference being had to the accompanying drawings, in which,

Fig. 1 is a vertical section of a telephone receiver of the watch case type, illustrating it as constructed in accordance with my invention;

Fig. 2 is a plan of the instrument shown in Fig. 1, the cap and diaphragm being removed;

Fig. 3 is a vertical section of a second form of watch case receiver, also showing it as equipped with my inventioni,

Fig. 4 is a plan of the interior of the instrument shown in Fig. 3;

Figs. 5 and 6 are a vertical section and a plan of the interior of a receiver of a loud speaking type, equipped with my invention;

Figs. 7 and 8 are respectively a. vertical sect-ion and a plan of another form of loud speaking receiver, also provided with my lll-VQIltlOIlj and Fig. 9 1s a fragmentary side elevation of a telephone instrument, illustrating the stop for the adjustable plug and the graduations for indicating the amount of its adjustment.

Referring to Figs. 1 and 20f the above drawings, 1 represents the casing of a watch case receiver which is closed at one end and has threaded on the opposite end a cap 2, clamping to it a diaphragm 3. In accordance with my invention I adjustably thread into the closed end of the case a plug 4 having a knurled head or flange 5 and having its inner end recessed for the reception of the central cylindrical portion or boss of a plate 6, which in the present instance is circular in outline. This plate carries the magnet 7 of the instrument, which is held to it-by screws 8 and on the central pole of said magnet is mounted the receiver coil 9 connected to terminals 10 and 11 mounted in the present instance in opposite sides of the case 1.

A series of studs 12, in the present instance four in number, is mounted in and extends parallel with the axis of the case 1, passing through suitable openings in the plate 6, which is thereby held from rotating. Each of said studs 12 has mounted on its inner end a cap or head in the form of a pair of cupped washers 13, between which and the plate 6 is mounted a coil spring 14 tending to force said plate away from the diaphragm and retain it in engagement with the plug t.

When it is desired to adjust the mechanism of the instrument, in the present instance to vary the air gap between the diaphragm 3 and the poles of the magnet 7 the rotation of the plug 4 by means of its head 5 will bodily move the plate 6 and with it said magnet and the coil 9 toward or from the diaphragm, and obviously this adjustment may be accomplished during operation of the receiver and without interfer} ing with its proper functioning. the plug 4 into the case will move the pole pieces and coil nearer the diaphragm against the action of the springs 14, while an opposite movement of said plug willpermit said springs to cause the plate 6 to slide on the studs 12 and to so move the magi 't away from the diaphragm. The central projection 15 of the plate serves to center this in the depression 16*o'f the plug and the studs not only'prevent rotation of the plate, but insure that it shall at all times remain parallel with the-diaphragm without possibility of tilting.

The various parts are so designed and arranged that one complete revolution of the plug 4 will constitute the desirable range of adjustment and in order to prevent further and undesirable movement of said plug I mount on it a stop 17 in such position as to cooperate'with the projection 18 on the flange 5 of the plug. I preferably form the case 1 with a projecting boss 19 concentric with the plug 4 and graduate it with a scale 20 as indicated. in Fig. 9. An

Screwing index mark 20 is also preferably formed on the edge of the flange to cooperate with this scale in indicating the adjustment of the diaphragm.

In Figs. 3 and at I have shown my invention as applied to a watch case receiver of difi'erent construction from that of Figs. 1 and 2, the magnet 7 in this instance be ing ring shaped in form and having two L-shaped pole pieces 21, on whose parallel arms are mounted the coils 9 of the instrument. As before, the magnet and coils are carried upon a plate 6 which in turn is acted upon by a series of springs 14 mounted on studs 12 and fixed on the bottom of the instrument. Said plate is carried on the adjustable plug 4 as previously described.

In Figs. 5 to 8 inclusive, I have illustrated my invention as applied to two forms of loud speaking telephone receivers which in each instance comprisea case 1 and a cap 2*, having an opening 23 for the reception of a horn. The diaphragm 3 as before is clamped between the cap and the case and, in the construction shown in Figs. 5 and ('3, is acted onv by a pair of coils 9* carried on two L-shaped pole pieces 21 associated with the circular magnet 7 Said coils and magnet, as in the other forms of my invention, are mounted upon a plate 6 carried on studs 12 and pressed toward the closed end of the case by coil springs 14 mounted on said studs. Said plate 6 is rotatably engaged by a plug 4* adj ust'ably threaded through a boss 19 at the center of the closed end of the case, so that as before the rotation of this plug will vary the distance between the pole pieces of the magnet and the diaphragm 3 In Figs. 7 and 8 I have shown my invention as applied to a second form of loud speaking receiver, in which there is provided a magnet 7 of the horse-shoe type, carried by and fixed to a plate 6 adjustable within the case 1 as previously described. This magnet has pivotally mounted within it an armature 24 on which are carried the coils 9 and one end of said armature is movable between the poles of said magnet while the other is connected through a link 25 with the diaphragm 3. If desired the boss 19 may he graduated as before described and also provided with a stop 17 mounted to coact with a projection 18 on the plug to limit the rotation of thelatter. In this latter case the adjustment of the plug in the case will as before vary the adjustment of the instrument as the distance of the armature from the poles of the magnet is varied.

In all of the above constructions the adjustment'anay be accomplished from the outside of the instrument and that without exposing its interior or permitting access to its electromagnetic elements.

I claim:

1. The combination in a telephone instrument of a case; a diaphragm; an electro magnetoperatively associated with said diaphragm; a plate carrying said magnet; a plug threaded into the case and engaging the plate, said plug constituting a bearing for said plate; and springs acting on the plate to force it away from the diaphragm.

2. The mml'iination in a telephone receiver of a case closed at one end and having a cap at the opposite end; a diaphragm clamped between the cap and the open eml of the case; an electromagnet operatively associated with the diaphragm; a plate carrying said magnet; a headed plug threaded into the closed end of the ease and engaging the plate; means acting on the plate for maintaining it in engagement with the plug in such manner as to provide a centering bearin'g therefor; and a stop for limiting rotation of the plug.

3. The combination in av telephone re ceiver of a case closed at one end and having a cap at the opposite end; a diaphragm clamped between the cap and the open end of the case; an electromagnet operatively associated with the diaphragm; a plate carrying said magnet; a headed plug threaded into the closed end of the case and engaging the plate, said plate having a centering boss, said plug having a recess adapted to re volubly receive said boss; means acting on the plate for retaining said boss in said recess; and a stop for limiting rotation of the plug.

4. The combination in a telephone instrument of a case; studs fixed to and extending within said case; a. plate slidable on the studs; telephonic mechanism on the plate; springs respectively mounted on the studs and acting to move the plate in one direction; and a longitudinally adjustable plug threaded into the case and formed at its inner end to receive a centering bOSS'GXtBHding from said plate, whereby the plate may be moved against the force of the springs.

JOHN S. TIMMON S. 

